title: First imaging results of an intraindividual comparison of (11)C-acetate and (18)F-fluorocholine PET/CT in patients with prostate cancer at early biochemical first or second relapse after prostatectomy or radiotherapy.
abstract: OBJECTIVE
  (18)F-Fluorocholine (FCH) and (11)C-acetate (ACE) PET are widely used for detection of recurrent prostate cancer (PC). We present the first results of a comparative, prospective PET/CT study of both tracers evaluated in the same patients presenting with recurrence and low PSA to compare the diagnostic information provided by the two tracers.
  
  
  METHODS
  The study group comprised 23 patients studied for a rising PSA level after radical prostatectomy (RP, 7 patients, PSA ≤ 3 ng/ml), curative radiotherapy (RT, 7 patients, PSA ≤ 5 ng/ml) or RP and salvage RT (9 patients, PSA ≤ 5 ng/ml). Both FCH and ACE PET/CT scans were performed in a random sequence a median of 4 days (range 0 to 11 days) apart. FCH PET/CT was started at injection (307 ± 16 MBq) with a 10-min dynamic acquisition of the prostate bed, followed by a whole-body PET scan and late (45 min) imaging of the pelvis. ACE PET/CT was performed as a double whole-body PET scan starting 5 and 22 min after injection (994 ± 72 MBq), and a late view (45 min) of the prostate bed. PET/CT scans were blindly reviewed by two independent pairs of two experienced nuclear medicine physicians, discordant subgroup results being discussed to reach a consensus for positive, negative end equivocal results.
  
  
  RESULTS
  PET results were concordant in 88 out of 92 local, regional and distant findings (Cohen's kappa 0.929). In particular, results were concordant in all patients concerning local status, bone metastases and distant findings. Lymph-node results were concordant in 19 patients and different in 4 patients. On a per-patient basis results were concordant in 22 of 23 patients (14 positive, 5 negative and 3 equivocal). In only one patient was ACE PET/CT positive for nodal metastases while FCH PET/CT was overall negative; interestingly, the ACE-positive and FCH-negative lymph nodes became positive in a second FCH PET/CT scan performed a few months later.
  
  
  CONCLUSIONS
  Overall, ACE and FCH PET/CT showed excellent concordance, on both a per-lesion and a per-patient basis, suggesting that both tracers perform equally for recurrent prostate cancer staging.
authors.affiliation: Nuclear Medicine Division, University Hospital of Geneva, 1211, Geneva 14, Switzerland, franz.buchegger@chuv.ch.
authors.forename: Franz
authors.initials: F
authors.lastname: Buchegger
authors.forename: Valentina
authors.initials: V
authors.lastname: Garibotto
authors.forename: Thomas
authors.initials: T
authors.lastname: Zilli
authors.forename: Laurent
authors.initials: L
authors.lastname: Allainmat
authors.forename: Sandra
authors.initials: S
authors.lastname: Jorcano
authors.forename: Hansjörg
authors.initials: H
authors.lastname: Vees
authors.forename: Olivier
authors.initials: O
authors.lastname: Rager
authors.forename: Charles
authors.initials: C
authors.lastname: Steiner
authors.forename: Habib
authors.initials: H
authors.lastname: Zaidi
authors.forename: Yann
authors.initials: Y
authors.lastname: Seimbille
authors.forename: Osman
authors.initials: O
authors.lastname: Ratib
authors.forename: Raymond
authors.initials: R
authors.lastname: Miralbell
mesh_terms: D000085:Acetates; D000368:Aged; D000369:Aged, 80 and over; D002250:Carbon Radioisotopes; D002794:Choline / Q000031:analogs & derivatives*; D005462:Fluorine Radioisotopes; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D049268:Positron-Emission Tomography; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000378:metabolism*; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000532:radiotherapy / Q000601:surgery; D014057:Tomography, X-Ray Computed
chemical_list: D000085:Acetates; D002250:Carbon Radioisotopes; D005462:Fluorine Radioisotopes; C514960:fluorocholine; D017430:Prostate-Specific Antigen; D002794:Choline